• Aucun résultat trouvé

Phenolic extracts of bilberry: they protect lipid from oxidation in in vitro simulated digestion conditions

N/A
N/A
Protected

Academic year: 2021

Partager "Phenolic extracts of bilberry: they protect lipid from oxidation in in vitro simulated digestion conditions"

Copied!
2
0
0

Texte intégral

(1)

HAL Id: hal-01608682

https://hal.archives-ouvertes.fr/hal-01608682

Submitted on 2 Jun 2020

HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Distributed under a Creative Commons Attribution - ShareAlike| 4.0 International License

Phenolic extracts of bilberry: they protect lipid from oxidation in in vitro simulated digestion conditions

Oana-Crina Bujor, Christian Ginies, Valentin I. Popa, Claire Dufour

To cite this version:

Oana-Crina Bujor, Christian Ginies, Valentin I. Popa, Claire Dufour. Phenolic extracts of bilberry:

they protect lipid from oxidation in in vitro simulated digestion conditions. ICP 2016 - XXVIIIth

International Conference on Polyphenols, Jul 2016, Vienna, Austria. 2016. �hal-01608682�

(2)

Phenolic extracts of bilberry: they protect lipid from oxidation in in vitro simulated

digestion conditions

Oana-Crina Bujor (a,b) , Christian Ginies (a) , Valentin I. Popa (b) , Claire Dufour (a)

a

UMR408 SQPOV "Safety and Quality of Plant Products", INRA, Université d'Avignon, F-84000 Avignon, France

b

“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 700050 Iasi, Romania

Centre Inra Provence-Alpes-Côte d’Azur 228 route de l’aérodrome

Domaine Saint Paul, Site Agroparc CS 40 509

84914 Avignon Cedex 9 http://www.paca.inra.fr

Polyunsaturated Fatty Acids

(TG, PL, chlolesterol esters) +

Dietary iron + O2, H+

Polyphenol consumption/day 0,8-1,3 g [1]

Polyphenols bioaccessibility [PP] natifs0,5 - 1 mM Lipid oxidation products

(LOOH, L=O, LOH…). [2]

Absorbed in LDL  Atherogenicity of modified LDL

BACKGROUND

Bilberry (BB) (Vaccinium myrtillusL.) polyphenols:

content and main contributors [3]

Stems 79 mg/g DE A-type trimer B-type dimer

5-O-Caffeoylquinic-acid Fruits

27 (H2O) mg/g DE 41 (aq. EtOH) mg/g DE delphinidin-3-O-glucoside Leaves

125 mg/g DE 5-O-Caffeoylquinic-acid

MATERIALS AND METHODS

oil-in-water Emulsionstabilized by:

- BSA (Bovine Serum Albumin) - PL(egg yolk phospholipids)

Metmyoglobin [20 μM]final

pH 5 (initial stage of digestion)

37 °C, 6 h Lipid-derived conjugated dienes

(CDs) Abs. at 234 nm stems

leaves

fruits [0.1 mg DE/mL]

[0.2 mg DE/mL]

BB samples from July 2013

Leaves

Stems

Fruits

References:

[1] Pérez-Jiménez J. et al., Am. J. Clin. Nutr., 2011, 93, 1220–8.

[2] Ursini F. and Sevanian A., Biol. Chem., 2002, 383, 599–605.

[3] Bujor et al., Food Chem, submitted.

[4] Lorrain et al., J Agric Food Chem., 2012, 60, 9074−9081.

[5] Minekus M. et al., Food & Function, 2014, 5, 1113-24.M

Oral Phase Gastric Phase Intestinal Phase

Mix:

dietary lipids (BSA or PL emulsions)

+ Leaf extract (36 mg)

+ CaCl2(0.75 mM)

Adjustment pH 7:

1 M NaOH

Incubation:

5 min, 37 °C, 130 rpm

No sampling

Oral phase (1:1 dilution with SGF)

+ pepsin (2000 U/mL)

+ MbFeIII(20 μM)

Adjustment pH 5:

1 M HCl

Incubation: Sampling:

1 h, 37 °C, 280 rpm; 0, 30, 60 min

Adjustment pH 3:

1 M HCl

Incubation: Sampling:

1 h, 37 °C, 280 rpm; 90, 120 min

Gastric phase (1:1 dilution with SIF)

+ pancreatin (100 U/mL)

+ bile (10 mM)

+ CaCl2(0.49 mM)

Adjustment pH 6.5:

1 M NaOH

Incubation:

2 h, 37 °C, 280 rpm

Sampling:

0, 30, 60, 90, 120 min

Determination of CDs Determination of CDs

In vitro model of oro-gastrointestinal digestion [5]

In vitro model of gastric digestion [4]

RESULTATS AND DISCUSSIONS

CONCLUSIONS

Leaf, stem and fruit extracts of bilberry can play a protective role towards oxidation of polyunsaturated dietary lipids during digestion.

The fast lipid oxidation in the gastric step (BSA and PL emulsion systems) and the slower lipid oxidation in the intestinal step (PL system) were totally inhibited by a bilberry leaf extract at the level of 3 mg/mL in the gastric step.

the stability of the phenolic compounds should be further evaluated in the gastrointestinal digestion to give an insight into their protective mechanisms.

Gastric digestion: Inhibition of lipid oxidation

Oro-gastrointestinal digestion: Inhibition of lipid oxidation

0 50 100 150 200 250 300

0 30 60 90 120

μmol CD / g lipids

Digestion time (min) Gastric step

0 100 200 300 400 500 600

0 30 60 90 120

μmol CD / g lipids

Digestion time (min)

Control Leaf extract Intestinal step

In BSA-stabilized emulsions

0 50 100 150

0 30 60 90 120

μmol CD / g lipids

Digestion time (min) Gastric step

0 100 200 300 400 500

0 30 60 90 120

μmol CD /g lipids

Digestion time (min)

Control Leaf extract Intestinal step

In PL-stabilized emulsions

Gastric step: lipid oxidation was 2-fold slower than in the BSA model. Totally inhibited by the stem extract.

Intestinal step: weak lipid oxidation. Antioxidant action of the leaf extract preserved.

Gastric step: fast lipid oxidation between t0 and 120 minmetmyoglobin was likely the prooxidant form for the 1st hour when hematin may be released from MbFeIII during the 2ndhour. The leaf extract at a dietary concentration (3 mg/mL) totally inhibited lipid oxidation.

Intestinal step: weak increase in CD levels from 162 to 226 μmol/g lipids over the two hours of study. Inhibition by the stem extract is kept.

1. Microwave-assisted extraction (1% citric acid in water

or 55% aq. EtOH (fruits only)

Extracts from leaves and stems appear similarly efficient at inhibiting metmyoglobin-initiated lipid oxidation in both BSA- and PL-stabilized emulsions at pH 5 (49-73%). Leaves containing 75%

(w/w) in chlorogenic acids proved to be the best antioxidant extract in the BSA model.

Extracts from fruit were added at twice the level compared to stem and leaf.

Extract with 55% aq. EtOH has a higher content in phenolic compounds and is also more efficient than the aqueous fruit extract.

Leaf and stem extracts have no ability to inhibit lipid oxidation at pH 3 in PL model (data not shown)

NB: standards were used at 100 μM levels.

Extracts of bilberry stems, leaves and fruits:

Can they protect dietary lipids from oxidation during digestion in in vitro conditions?

2. Dried Extracts (DE)

0 20 40 60 80 100 120

Leaves Stems Fruit/water Fruit/EtOH55% Chlorogenic acid (–)-Epicatechin Procyanidin A2 Cyanidin-3-gal.

% Inhibition over 4 h

BSA model PL model

Références

Documents relatifs

All six of these transcripts were significantly more abundant in plants grown at high CO 2 , pointing to the activation of oxidative signaling in these conditions (Fig. 6B)..

Free fatty acids (FFA) released during the simulated duodenal digestion of raw oat groat (yellow lines), flakes (red lines) and flour (blue lines) at concentrations corresponding

Total lipid release (%) from muffins containing almond flour (AF, n = 3) or almond particles (AP, n = 3) after mastication, in vitro gastric and gastric plus duodenal digestion

regime and at low driving-frequency, a single-electron source can be described in terms of a quantum RC cir- cuit whose charge relaxation resistance has a universal..

key words - International Labor Organization, - Sustainable Development, - United Nations, - Gender Equality, - Decent Work, - Globalization.. 86 ﺔﻣدﻘﻣ :

This study demonstrates that an LBBB activation sequence in patients is associated with ~33% lower unipolar voltage amplitudes in the septum, and that these regional voltage

It is based upon an ontology to model the domain knowledge and a learning method to build the interpretable models (decision trees in this paper).. Subjective and objective

Lipid oxidation and its inhibition by apple polyphenols in static and dynamic in vitro digestion systems.. Gaëtan Boléa, Pascale Goupy, Christian Ginies,